JP2002040776A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming device where a one component developing device can be made small sized, deterioration of one component developer utilized for the one component developing device can be prevented and service life before exchange of the one component developing device can be made appropriate. SOLUTION: In the image forming device, it is characteristic that a level detecting means to detect the level of the one component developer inside the one component developing device is provided as well as a developer storing container that can be separated from the one component developing device, the one component developer is fed from the developer storing container according to the detected level of the level detecting means and the level of the one component developer inside the one component developing device is controlled to be constant.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus using a one-component developing apparatus used for forming an electrophotographic image such as a copying machine, a printer, a facsimile, and the like.

[0002]

2. Description of the Related Art Conventionally, a developing device has been used in an electrophotographic image forming apparatus such as a copying machine, a printer, a facsimile or the like. For example, the present inventors carry and transport a one-component developer (toner), and supply the one-component developer to an image forming body (for example, a photosensitive drum used for electrophotography). A developing device for supplying a one-component developer (toner) to a developer carrying member (developing sleeve) from a developer accommodating section by using a supply roller is disclosed in Japanese Patent Application No. 11-110,086.
No. 131263.

On the other hand, as one method of forming a multi-color image, charging, image exposure and development for each color are sequentially performed within one rotation of one image forming body (photosensitive drum) to form a color image. Although the color image forming apparatus to be formed is used, the present inventors have arranged and used a plurality of one-component developing devices around an image forming body (photosensitive drum) in such a color image forming apparatus. A color image forming apparatus in which the plurality of one-component developing devices are reduced in size is proposed, for example, in Japanese Patent Application Laid-Open No. Hei 5-307307.

[0004]

However, in a conventional one-component developing device used in an image forming apparatus, a developer accommodating portion is provided integrally, and the one-component developer (toner) in the developer accommodating portion is eliminated. When the one-component developing device is replaced, a large amount of toner is
Although the toner is replenished each time, the toner replenished at the time of being involved stays for a long time while being agitated in the developer accommodating portion, so that toner deterioration is a serious problem. In addition, according to the life of the one-component developing device, with the toner stored,
There is also a problem that the one-component developing device has to be replaced and that when the toner runs out, the one-component developing device must be replaced before the one-component developing device reaches its end of life. Further, the need for a large developer accommodating section causes a problem that the size of the one-component developing device is increased,
In particular, this is a problem in the above-described proposed color image forming apparatus that requires a one-component developing device to be downsized.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems, reduces the size of a one-component developing device, prevents deterioration of a one-component developer used in the one-component developing device, and optimizes the replacement life of the one-component developing device. It is an object of the present invention to provide an image forming apparatus that is designed to be used in various ways.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to provide a developer carrier that holds and rotates a thin layer of a one-component developer, and a supply roller that supplies and recovers the developer to and from the developer carrier. In an image forming apparatus having a one-component developing device that stores the one-component developer, a level detecting unit that detects a level of the one-component developer in the one-component developing device is provided, and the one-component developing device includes: A detachable developer storage container is provided, and a one-component developer is supplied from the developer storage container according to a detection level of the level detection unit, and a level of the one-component developer in the one-component developing device is adjusted. This is achieved by an image forming apparatus characterized in that it is controlled to be constant.

[0007]

Embodiments of the present invention will be described below. Note that the description in this column does not limit the technical scope of the claims and the meaning of terms. Further, the following assertive description in the embodiment of the present invention indicates the best mode, and does not limit the meaning or technical scope of the terms of the present invention. In the following description of the embodiment, when a color toner image is transferred to a transfer material, the color toner image is transferred to the surface of the transfer material facing the image forming body in the transfer area (referred to as the surface or upper surface of the transfer material). The image is a front image, the other side of the transfer material (called the back or bottom surface of the transfer material)
The image to be transferred to is referred to as a backside image.

An image forming process and each mechanism of an embodiment of an image forming apparatus using a developing device according to the present invention will be described with reference to FIG. 1 or FIG. FIG. 1 is a cross-sectional configuration diagram of a color image forming apparatus according to an embodiment of an image forming apparatus using a developing device according to the present invention.
FIG. 3 is an enlarged cross-sectional configuration diagram illustrating a developing device used in the image forming apparatus of the present invention and a first example of a developer container.
In the color image forming apparatus shown in FIG. 1, a belt-shaped intermediate transfer member is provided, and toner images are formed on both surfaces of a transfer material using the belt-shaped intermediate transfer member, and the toner images are collectively fixed. Although a double-sided image forming apparatus is used, the present invention is not limited to double-sided image forming. Further, the present invention is not limited to a color image forming apparatus, but is also applicable to a monochrome image forming apparatus.

Referring to FIG. 1, a photosensitive drum 10 serving as an image forming body is provided with a cylindrical base formed of, for example, a transparent member made of optical glass or transparent acrylic resin inside.
Transparent conductive layer, a-Si layer or organic photosensitive layer (OP
A photosensitive layer such as C) formed on the outer periphery of the substrate;
It is rotated clockwise as shown by the arrow in FIG.

Scorotron charger 11 as charging means
Is used in an image forming process of each color of yellow (Y), magenta (M), cyan (C) and black (K), and is exposed in a direction orthogonal to a moving direction of the photosensitive drum 10 as an image forming body. A control grid fixed to a predetermined potential with respect to the above-mentioned organic photosensitive layer of the photoconductor drum 10 and a discharge electrode 11a formed of, for example, a saw-tooth electrode; A charging action (minus charging in the present embodiment) is performed by polar corona discharge, and a uniform potential is applied to the photosensitive drum 10. Other wire electrodes can be used as the discharge electrode 11a.

The exposure unit 12 as an image exposure means for each color is arranged such that the exposure position on the photosensitive drum 10 is located between the discharge electrode 11a of the scorotron charger 11 and the developing position of the developing unit 13. Be placed.

The exposure unit 12 is a linear exposure element 12a in which a plurality of LEDs (light emitting diodes) as image exposure light emitting elements arranged in the main scanning direction in parallel with the axis of the photosensitive drum 10 are arranged in an array. And a selfoc lens 12b as an equal-magnification imaging element are configured as an exposure unit attached to a holder (not shown), attached to the holding member 20, and housed inside the base of the photosensitive drum 10. By configuring the exposure unit as a unit, it is possible to reduce the size of the image forming body and to perform highly accurate alignment between the color toner images. Image data of each color read by a separate image reading device and stored in the memory is sequentially read from the memory and input to the exposure unit 12 for each color as an electric signal.

As the exposure element, an element in which a plurality of light-emitting elements such as FL (phosphor emission), EL (electroluminescence), and PL (plasma discharge) are arranged in an array is used. The light emission wavelength of the light emitting element used in this embodiment is generally in the range of 780 to 900 nm, which is high in the transmittance of the Y, M, and C toners when performing image exposure from the outside. Since the exposure method is used, a shorter wavelength of 400 to 780 nm, which does not sufficiently transmit light to the color toner, may be used.

A developing unit 13 provided in accordance with the color order in which an image is formed and the rotating photosensitive drum is provided in accordance with the color order.
In the present embodiment, the Y and M developing units 13 are on the left side of the photosensitive drum 10 and the C and K developing units 13 are on the right side of the photosensitive drum 10 with respect to the photosensitive drum 10 of FIG. The Y and M scorotron chargers 11 are arranged below the Y and M developing units 13, and the C and K scorotron chargers 11 are arranged above the C and K developing units 13.
The Y and M developing units 13 are symmetrical to the C and K developing units 13 with respect to a vertical plane passing through the center axis of the photosensitive drum 10.

Developing device 1 as a one-component developing device for each color
3 is yellow (Y), magenta (M), cyan (C)
And a one-component developer (toner) of black (K), respectively, and is rotated in the same direction as the rotation direction of the photosensitive drum 10 at the developing position while maintaining a predetermined gap with respect to the peripheral surface of the photosensitive drum 10. And a developing sleeve 131 as a developer carrier.

A developing device 13 is provided with a gap of a predetermined value, for example, 100 μm, from the photosensitive drum 10 by an abutting roller (not shown).
In the developing operation of the developing unit 13 for each color, a developing bias to which a DC voltage or an AC voltage is applied is applied to the developing sleeve 131, so that one component contained in the developing unit is accommodated. Jumping development by the developer is performed, and the photosensitive drum 1 is negatively charged.
A non-contact reversal development is performed by applying a DC bias having the same polarity as that of the toner to 0 (minus polarity in the present embodiment) to attach the toner to the exposed portion. At this time, the precision of the development interval needs to be about 20 μm or less in order to prevent image unevenness.

A supply roller 132, which is a toner supply member, is provided in contact with the developing sleeve 131.
The supply and collection of the toner to the developing sleeve 131 are performed by 32. The charge amount of the toner used during development is 1
It is preferably around 0 to 20 μC / g.

Reference numeral 133 denotes a blade which is a developer regulating member, and reference numeral 134 denotes a stirring screw which is a stirring member for stirring the toner in the developing device 13. Further, a toner supply hopper 600 as a developer storage container containing a developer is provided on the upper side of the developing device 13 so as to be separable from the developing device 13. Is supplied. LSa is a level sensor that is a level detecting unit that detects the level of the toner in the developing device 13, and is provided on the side of the stirring member 134 of the developing casing 138. The toner is the developing sleeve 131 and the blade 13
3. The toner is frictionally charged between the supply rollers 132.

The developing unit 13 for each color described above converts the electrostatic latent image on the photosensitive drum 10 formed by the charging by the scorotron charger 11 and the image exposure by the exposure unit 12 into a non- In a non-contact state by the contact developing method, reversal development is performed with toner having the same polarity as the charged polarity (in the present embodiment, the photosensitive drum is negatively charged and has negative polarity).

As the one-component developer (toner) used in the developing device 13 as the one-component developing device, a spherical insulating toner obtained by the same method as the conventional toner can be used. Spherical toners are preferred for enhancing developability and obtaining high quality images. Preferred toners are styrene resin, vinyl resin, ethylene resin, rosin modified resin, acrylic resin, polyamide resin, epoxy resin,
Conventionally known toner particles are manufactured by using a polymerizing agent of a resin such as a polyester resin or a resin such as a fatty acid wax such as palmitic acid and stearic acid, and adding a coloring component such as a color pigment and a charge control agent as necessary. It is made of particles having an average particle size of 20 μm or less, preferably 10 μm or less, particularly preferably 7 μm, which can be produced by the same method as the above method. If necessary, a fluidizing agent for improving the fluidity of the particles and a cleaning agent useful for cleaning the surface of the image forming body are mixed. As a fluidizing agent, colloidal silica, silicon varnish, metal soap, a nonionic surfactant, or the like can be used.As a cleaning agent, a surfactant such as a fatty acid metal salt, organic group-substituted silicon, or fluoric acid can be used. Can be used.

As described above, the developer accommodating container can be separated, and the developing device 13 is miniaturized, and the Y, M, C, and K small developing devices 13 containing a one-component developer are used.

An image read by an image pickup device of an image reading apparatus separate from the apparatus or an image edited by a computer is temporarily stored as image data of each color of Y, M, C and K as a document image. And stored.

When the image recording starts, the photosensitive drum driving motor (not shown) starts to rotate the photosensitive drum 10 in the clockwise direction indicated by the arrow in FIG. 1 and simultaneously develops yellow (Y) on the left side of the photosensitive drum 10. Y arranged below the vessel 13
The application of a potential to the photosensitive drum 10 is started by the charging action of the scorotron charger 11 described above.

After a potential is applied to the photosensitive drum 10, exposure by the first color signal, that is, an electric signal corresponding to Y image data is started in the Y exposure optical system 12, and the rotational scanning of the photosensitive drum 10 is performed. As a result, an electrostatic latent image corresponding to the Y image of the original image is formed on the photosensitive layer on the surface.

The latent image is reversal-developed by the Y developing device 13 in a state where the developer on the developing sleeve 131 is not in contact with the developer, and a yellow (Y) toner image is formed in accordance with the rotation of the photosensitive drum 10.

Next, the photosensitive drum 10 is placed on the yellow (Y) toner image, and further on the left side of the photosensitive drum 10 and above the yellow (Y), a magenta (M) developing device 1 is provided.
A potential is applied by the charging action of the magenta (M) scorotron charger 11 disposed below the M.3, and exposure by an electrical signal corresponding to the second color signal of the M exposure optical system 12, that is, M image data is performed. The magenta (M) toner image is formed on the yellow (Y) toner image by non-contact reversal development by the M developing unit 13.

By the same process, a cyan (C) scorotron charger 11, a C exposure optical system 12 and a C developer are arranged on the right side of the photosensitive drum 10 above the cyan (C) developer 13. 13 further causes a cyan (C) toner image corresponding to the third color signal to appear on the right side of the photoreceptor drum 10 and below the black (K) developing unit 13 below the black (K) developing unit 13. ) Scorotron charger 11,
A black (K) toner image corresponding to the fourth color signal is sequentially formed by the exposure optical system 12 and the developing device 13, and a color toner image is formed on the peripheral surface thereof within one rotation of the photosensitive drum 10. Is formed.

These Y, M, C and K exposure optical systems 12
Exposure to the organic photosensitive layer of the photosensitive drum 10 is performed from the inside of the drum through the transparent substrate described above.
Therefore, the exposure of the image corresponding to the second, third, and fourth color signals is performed without any influence from the previously formed toner image, and the same exposure as the image corresponding to the first color signal is performed. It is possible to form an electrostatic latent image.

By the above-described image forming process, a superimposed color toner image serving as a back side image is formed on the photosensitive drum 10 (image forming body) as an image forming body, and the superimposed color toner of the back side image on the photosensitive drum 10 is formed. In the transfer area 14b, the toner image is transferred between the drive roller 14d and the driven roller 14e by a primary transfer device 14c (first transfer means) to which a DC voltage having a polarity opposite to that of the toner (positive polarity in this embodiment) is applied. Intermediate transfer belt 14a which is provided in the vicinity of or in contact with the photosensitive drum 10
(Intermediate transfer member).

The toner remaining on the peripheral surface of the photosensitive drum 10 after the transfer is removed by the cleaning device 19 or the cleaning blade 19a made of a rubber material which is in contact with the photosensitive drum 10, and then the next surface image is removed. Is performed.

After the superimposed color toner image serving as the back side image is formed on the intermediate transfer belt 14a as described above, the superimposed toner image serving as the front side image is continuously formed on the photosensitive drum 10. It is formed in the same manner as the forming process. At this time, the intermediate transfer belt 14
The back image formed on the photosensitive drum 10 and the back image formed on the photosensitive drum 10 are synchronized with each other in the transfer area 14b, and the toner images are formed on both sides. It is necessary to change the image data so that the front surface image formed at this time is a mirror image of the back surface image formation on the photosensitive drum 10.

The recording paper P, which is a transfer material, is sent out by a feed roller 15a from a paper feed cassette 15, which is a transfer material storage means, is fed by a feed roller 15b, and is conveyed to a timing roller 15c.

The recording paper P is driven by a timing roller 15c to form a color toner image of a front image carried on the photosensitive drum 10 and a color toner image of a back image carried on the intermediate transfer belt 14a. The paper is fed to the transfer area 14b in synchronization. At this time, the recording paper P is charged to the same polarity as the toner by the paper charger 14f as the transfer material charging means, is attracted to the intermediate transfer belt 14a, and is fed to the transfer area 14b. By charging the paper with the same polarity as the toner, the recording paper P is prevented from attracting to the toner image on the intermediate transfer belt 14a or the toner image on the photosensitive drum 10 outside the transfer section, and the disturbance of the toner image is prevented. Preventing. The transfer material charging means includes an intermediate transfer belt 1
It is also possible to use a conductive roller, a brush charger, a corona charger, or the like that can make contact with and release contact with 4a.

A surface image on the peripheral surface of the photosensitive drum 10 is collectively collected by a primary transfer unit 14c as a first transfer unit to which a voltage having a polarity opposite to that of the toner (positive polarity in the present embodiment) is applied. The image is transferred onto the upper surface side (front surface side) of the recording paper P. At this time, the back side image on the peripheral surface of the intermediate transfer belt 14a is not transferred to the recording paper P and the intermediate transfer belt 14a
Exists. Next, a backside image on the peripheral surface of the intermediate transfer belt 14a is collectively recorded by a secondary transfer unit 14g as a second transfer unit to which a voltage having a polarity opposite to that of the toner (positive polarity in the present embodiment) is applied. The image is transferred to the lower surface (back surface) of the paper P.

Since the toner images of the respective colors overlap each other, it is preferable that the upper and lower toner layers of the toner layer are charged to the same polarity with the same charge amount in order to enable batch transfer. Accordingly, in a double-sided image formation in which the polarity of the color toner image formed on the intermediate transfer belt 14a is inverted by corona charging or the polarity of the color toner image formed on the photosensitive drum 10 is inverted by corona charging, the lower layer is formed. The toner is not sufficiently charged to the same polarity, so that the transfer becomes unfavorable.

The reversal development is repeated on the photoreceptor drum 10, and the color toner images of the same polarity formed by superposition are collectively transferred to the intermediate transfer belt 14a without changing the polarity, and then the recording paper is changed without changing the polarity. The batch transfer to P is preferable because it contributes to the improvement of the transferability of the backside image formation. Also for the surface image formation, reversal development is repeatedly performed on the photosensitive drum 10 to collectively transfer color toner images of the same polarity formed by superimposition onto the recording paper P without changing the polarity.
It is preferable because it contributes to improvement of the transferability of surface image formation.

As described above, in the color image formation, the first transfer means is operated to form a color toner image on the surface of the transfer material by using the above-described image forming method for the front surface and the back surface. A two-sided image forming method of forming a color toner image on the back surface of the transfer material by operating the second transfer means is preferably employed.

The intermediate transfer belt 14a, which is an intermediate transfer member, is an endless rubber belt having a thickness of 0.5 to 2.0 mm, and is made of silicon rubber or urethane rubber at 10 ⁸ to 10 ¹² Ω · cm.
And a two-layer structure in which a fluorine coating having a thickness of 5 to 50 μm is applied to the outside of the rubber substrate as a toner filming preventing layer. This layer also preferably has a similar semiconductivity. Instead of the rubber belt substrate, semiconductive polyester, polystyrene, polyethylene, polyethylene terephthalate, polyimide, or the like having a thickness of 0.1 to 0.5 mm can also be used.

The recording paper P on which the color toner images are formed on both sides is neutralized by a transfer material neutralizer 14h as a transfer material separating means, separated from the intermediate transfer belt 14a, and has a heater inside both rollers. The sheet is conveyed to a fixing device 17 as fixing means constituted by book rollers. By applying heat and pressure between the fixing roller 17a and the pressure roller 17b, the toner adhered to the front and back of the recording paper P is fixed, and the recording paper P on which double-sided image recording has been performed is sent by the paper discharge roller 18. And discharged to a tray outside the apparatus.

The toner remaining on the peripheral surface of the intermediate transfer belt 14a after the transfer is provided in an intermediate transfer belt cleaning device 14 as a cleaning means for the intermediate transfer belt, and can be brought into contact with and released from the intermediate transfer belt 14a. The cleaning is performed by the intermediate transfer belt cleaning blade 14i. Further, the toner remaining on the peripheral surface of the photoconductor drum 10 after the transfer enters the cleaning device 19 or is scraped off into the cleaning device 19 by a cleaning blade 19a made of a rubber material abutting on the photoconductor drum 10. The toner is collected in a waste toner container (not shown). The photosensitive drum 10 from which the residual toner has been removed by the cleaning device 19 is uniformly charged by the Y scorotron charger 11, and enters the next image forming cycle.

By using the above-described method, since the superimposed color toner image is transferred at a time, color misregistration of the color image on the intermediate transfer belt, scattering and rubbing of the toner, and the like are less likely to occur, and the image deterioration is small. Double-sided color image formation is performed.

According to FIG. 2, the developing device 13 as a one-component developing device for each color includes yellow (Y), magenta (M),
In this embodiment, cyan (C) and black (K) negatively charged one-component developers (toners) are accommodated, respectively, and are not in contact with the peripheral surface of the photosensitive drum 10 at a certain interval. And a developing sleeve 131 as a developer carrier that rotates in the rotation direction (clockwise direction in FIG. 2) and the forward direction (counterclockwise direction in FIG. 2) of the photosensitive drum 10 at the development position. A supply roller 132 as a toner supply member is provided in contact with the developing sleeve 131,
The supply roller 132 supplies toner to the developing sleeve 131 and collects toner from the developing sleeve 131. The supply roller 132 is provided in the supply section in parallel with the developing sleeve 131, and
(The counterclockwise direction in FIG. 2). Further, the toner in the developing device 13 is stirred by a stirring screw 134 serving as a stirring member which is rotated in the same direction as the supply roller 132 (counterclockwise direction in FIG. 2).

Developing sleeve 131 as a developer carrier
Is kept in non-contact with the peripheral surface of the photosensitive drum 10 with a predetermined value gap, for example, 100 μm to 500 μm, by an abutting roller (not shown). For example, a cylinder having a thickness of 0.3 mm to 0.5 mm and an outer diameter of 10 to 20 mm, for example, aluminum, stainless steel, or the like, which rotates in the rotation direction (clockwise direction in FIG. 2) and the forward direction (counterclockwise direction in FIG. 2). Made of non-magnetic material, the surface of which is sandblasted to JIS10
Indicated by point average roughness (JIS-B0610), 0.5
This is a roller member which has been subjected to a roughening process of μm to 5 μm and is rotatably supported. At the time of development, a non-contact one-component inversion development is performed by applying a DC bias of the same polarity (minus polarity in the present embodiment) to the developing sleeve 131 and a developing bias superimposed on an AC voltage. Then, the toner of the negative polarity on the developing sleeve 131 is attached to the latent image portion (image portion) on the photosensitive drum 10 to form a toner image on the latent image portion on the photosensitive drum 10.

Supply roller 132 as a toner supply member
Is the outside (outer periphery) of a conductive core (not shown) such as stainless steel.
Surface), foamed rubber such as urethane or silicon, volume resistance
Is 10 ⁶Ω · cm foam rubber layer (not shown)
Is done. During development, the supply roller 132 is used.
The same polarity as the toner polarity used (in this embodiment,
Negative polarity DC voltage supply roller bias is applied
You.

The blade 133, which is a developer regulating member,
For example, it is constituted by a strip-shaped elastic plate 133a made of a plate-like stainless steel having a thickness of about 0.1 mm and a rubber plate 133b provided on the elastic plate 133a and using, for example, urethane rubber. The projection 138b is attached and supported. The blade 133 abuts the rubber plate 133b at the distal end with the developing sleeve 131, and is disposed upstream in the rotation direction of the developing sleeve 131.
The blade 133 is a so-called counter type developer regulating member that regulates the height and amount of the developer layer (toner layer) on the developing sleeve 131. The blade 13
As for No. 3, a so-called trail-type developer regulating member whose tip is arranged downstream in the rotation direction of the developing sleeve 131 can also be used. The blade 133 forms a thin developer layer of about one or two layers on the developing sleeve 131.

The stirring screw 134, which is a stirring member,
An elliptic screw made of a metal member or a resin member is used to rotate the screw. The screw is disposed obliquely above the supply roller 132 to stir the toner in the developing device 13 and to make the interface Sa of the toner above the supply roller 132 uniform. To

For example, a level sensor LSa as a level detecting means using a sensor using capacitance detection (C detection)
Is provided on the side of the stirring screw 134 of the developing casing 138, detects the level of the interface Sa of the toner in the developing device 13, and controls the supply of toner from the developer storage container through a control unit (not shown).

At the corner of the upper surface of the developing casing 138 of the developing device 13, a rectangular opening 13 is formed in parallel with the developing device 13.
8a is provided, a toner supply hopper 600 as a developer storage container is fitted into the opening 138a, and the toner supply hopper 600 is provided detachably (removably) from the developing device 13. Casing 610 of toner supply hopper 600
An opening 1 for supplying toner from the toner supply hopper 600 is provided at a side end bottom portion connected to the opening
A cylindrical sponge roller 614 parallel to 38a is provided. A rectangular leveling plate 612 made of, for example, a mylar sheet or phosphor bronze is provided on the upstream side in the rotation direction of the sponge roller 614, and a rectangular flattened member is provided on the downstream side. A scraping plate 613 made of a mylar sheet is provided, for example, by sticking, and the sponge roller 614 is closed from both sides by the leveling plate 612 and the scraping plate 613.
The toner is held inside the toner supply hopper 600.
When the level of the interface Sa of the toner in the developing device 13 is detected by the level sensor LSa and becomes lower than a predetermined level stored in the ROM of the storage unit (not shown), the toner is transmitted through the control unit (not shown). The stirring lever 611 inside the supply hopper 600 is rotated, and the toner is supplied from the toner supply hopper 600 by the rotation of the sponge roller 614 that is rotated in synchronization with the stirring lever 611. The toner that has fallen from the sponge roller 614 through the opening 138a falls into the developing device 13 and falls on the stirring screw 134.

In the above, replacement of the toner supply hopper 600 or replacement of the developing unit 13 which has reached the end of its life when the toner is used up is performed by opening the opening / closing cover CV of the apparatus main body shown in FIG. In the above description, the scorotron charger 11 arranged on the upstream side of the developing device 13 in the rotation direction of the photosensitive drum 10 and the toner supply hopper 600 or the developing device 13 described with reference to FIG. , Can be exchanged together.

As described above, the developer accommodating container can be separated, so that a small-sized one-component developing device containing a one-component developer (toner) can be realized, and the toner stays in the one-component developing device for a long time. To prevent toner deterioration. When the toner in the developer container (toner supply hopper) is used up, only the toner supply hopper is replaced. Further, the loss of toner is reduced according to the life of the one-component developing device, and the one-component developing device can be replaced. Further, by integrating the charging means and the developer container or the one-component developing device and exchanging them together, uneven charging due to contamination of the charging means, particularly toner contamination caused by the developing means disposed close to the charging means. Uneven charging can be prevented.

Next, a second example of the developer accommodating container detachably provided in the one-component developing apparatus will be described with reference to FIGS. FIG. 3 is a second view of the developer container.
FIG. 4 is a perspective view of the developer accommodating container of FIG. 3, and FIG. 5 shows a state in which the developer accommodating container of FIG. FIG. 6 is a view showing a movement path of toner from the developer storage container shown in FIG. 5, and FIG. 7 is a front view of a solid lid of the developer storage container shown in FIG. 8 is a right side view of the solid lid shown in FIG. 7, FIG. 9 is a cross-sectional view taken along the line II in FIG. 7, and FIG. 10 is a sectional view of the solid lid shown in FIG. It is a figure which shows the state rotated 90 degrees from FIG.

According to FIGS. 3 to 10, as shown in FIG. 3, the developing device 13 which is a developer carrier has a structure similar to that described with reference to FIG.
The developing unit 13 is provided by a level sensor LSa which is a level detecting unit provided on a side portion of the stirring screw 134 of the C.T.
The level of the interface Sa of the toner inside is detected, and when the interface Sa becomes equal to or lower than a predetermined level stored in the ROM of the storage unit (not shown), a toner bottle as a developer storage container is passed through a control unit (not shown). Replenishment of toner from 30 is performed.

An opening 138 a is provided on the upper surface of the developing casing 138 of the developing device 13. The opening 138 a is provided with a storage container mounting portion 4 detachable (separable) from the developing device 13.
The toner bottle 30 as a developer storage container is fitted into the storage container mounting portion 40, and the toner bottle 30 is provided detachably (removably) from the storage container mounting portion 40. The toner bottle 30 can also be detached (separated) from the developing device 13 with the storage container mounting portion 40 integrated therewith. As will be described in detail later, the toner replenished from the toner bottle 30 is transported by the transport screw 43 and falls onto the stirring screw 134 through the opening 50 of the storage container mounting section 40.

Toner bottle 30 as developer container
As shown in FIG. 4, has a cylindrical shape, and a helical projection 31 protruding from the inner peripheral surface of the cylindrical portion is formed in the cylindrical portion. As will be described later, the projections 31 move the stored toner from the bottom of the container, that is, the upper right portion in FIG. 4 to the container opening, that is, the lower right portion by rotating the toner bottle 30. At the mouth of the toner bottle 30, a detachable solid lid 32 and an elastic
3 are provided.

FIG. 5 shows a state where the toner bottle 30 is mounted on the storage container mounting section 40. The mounting of the toner bottle 30 is performed by screwing a screw provided on the outer periphery of the solid lid 32 into the container receiving member 44 of the storage container mounting portion 40. In this mounting state, the extendable lid 33 of the toner bottle 30 abuts against a wall 421 provided on the container receiving member 44 of the storage container mounting section 40 and is compressed as shown to form a part of the solid lid 32. An opening that allows the passage of the toner is formed between the front end cover 327 and the front end cover 327. In addition,
As shown in FIG. 4, when the toner bottle 30 is not mounted on the storage container mounting portion 40, the elastic cover 33 is in close contact with the distal end cover 327 by its own elasticity.
The toner does not flow out of the printer.

Next, the toner supply mechanism will be described. The toner in the toner bottle 30 moves from the right to the left along the bottom of the cylindrical portion of the toner bottle 30 by the rotation of the toner bottle 30 by the feeding action of the projection 31. At the mouth of the toner bottle 30, that is, at the right end, the toner is scraped out by scraping members 321 and 322 provided on the solid lid 32. The scraped toner is transported on the slope 323,
It slides down on 324, falls on the transport screw 43, is transported by the transport screw 43, and is supplied to the developing device 13 through the opening 50. That is, as shown in FIG. 6, the toner, which is a one-component developer, passes through the toner bottle 30, the scraping members 321, 322, the conveying slopes 323, 324, the conveying screw 43, and the opening 50 in the order of the developing device 13 as shown in FIG.
Will be replenished. Conveying screw 43 and toner bottle 30
Are driven and rotated by the same motor (not shown).

The scraping action of the scraping members 321 and 322 will be described. Each member for scraping out the toner from the toner bottle 30 is provided on a solid lid 32. As shown in FIG. 7, a front view of the solid lid 32 from which the elastic lid 33 is removed is provided on a cylindrical lid base. Scraping members 321, 32
2. It is composed of the conveying slopes 323, 324 and the tip cover 327. The scraping members 321 and 322 have slopes inclined in opposite directions. As shown in FIG. 7 and FIG. 10 in which the fixed lid 32 is rotated by 90 ° in the rotation direction indicated by A from FIG. 7, the conveying slopes 323 and 324 are scraped out by the scraping members 321 and 3.
22 with respect to the rotation direction A of the solid lid 32 with respect to the slope 22
It is provided with a 0 ° phase shift. 7 and 10,
The white arrow indicates the direction of inclination of the slope, and the direction of the arrow indicates the direction of falling in a direction perpendicular to the paper surface. Although not shown, a toner opening through which toner passes is formed between the scraping members 321 and 322 and the conveying slopes 323 and 324.

As shown in FIG. 8, on the solid lid 32, scraping members 321 and 322 are provided symmetrically about the rotation axis of the toner bottle 30, and their slopes are opposite to each other as shown in FIG. (The white arrow in FIG. 8 indicates the direction of the inclination of the scraping member, and the direction of the arrow is the downward direction of the inclination.) FIG.
As shown in the figure, the scraping member 321 is formed with the slope and the side wall 321a, the arc-shaped wing 321b extending in the circumferential direction.
And the central wall 321d form a toner holding space E1 for holding toner. Similarly, the scraping member 322
Is its own slope, side wall 322a, arc-shaped feather 322b,
And the central wall 322d forms a toner holding space E2. When the toner bottle 30 rotates, the solid lid 32 is indicated by an arrow A.
9, the toner is scooped up by the arcuate wings 322b as shown in FIG.
And transported.

The operation of transporting the toner scraped by the scraping members 321 and 322 to the transport screw 43 will be described.

FIG. 10 shows a state in which the solid lid 32 has been rotated by 90 ° from the state shown in FIG. 7, and as is apparent from FIGS. 7 and 10, the conveying slopes 323, 323 with respect to the scraping members 321, 322. 324 are provided with a phase difference of 90 °. The transport slope 323 and the transport slope 324 are inclined in opposite directions.

Further, as shown in FIG.
The receiving member 44 for detachably receiving the solid lid 32 is rotatably provided in the storage container mounting portion 40, and the gear 4
7 is fixed. The gear 4 is driven by a motor (not shown).
7, the receiving member 44 and the toner bottle 30 rotate as shown by the arrow A, and the solid lid 32 also rotates.

With this rotation, the toner scooped up by the arcuate wings 321a of the scraping member 321 shown in FIG. 9 and the toner held in the holding space E1 is scraped by the scraping member 321.
As shown in FIG. 5, at the rotation position where the slope becomes lower left,
It falls on the slope, and falls on the transport slope 323. Similarly, the toner scraped by the scraping member 322 falls on the conveying slope 324.

As shown in FIG. 10, the conveying slope 323 is formed so as to have a 90 ° delayed phase with respect to the scraping member 321 so as to have a slope descending to the left, and receives the toner dropped from the scraping member 321. And transport screw 4
3 (see FIG. 5). Similarly, the transport slope 324 receives the toner dropped from the scraping member 322 and transports the toner onto the transport screw 43 (see FIG. 5).

As described above, the toner moves along the movement path from the toner bottle 30 to the transport screw 43 as shown by the arrow B in FIG.

The transport screw 43 is rotated by a gear 431 driven by a motor (not shown) together with the toner bottle 30 to transport the toner from left to right in FIG. 5 and to the developing unit 13 (see FIG. 3). Opening 50, which is the supply section
Transport to

The developing device 13 (see FIG. 3) is provided with the level sensor LSa for detecting the toner level in the developing device 13 as described above, and receives a signal from the level sensor LSa as the level detecting means. Toner bottle 30,
The solid lid 32 and the conveying screw 43 are rotated to supply toner. The scraping member 321 and the scraping member 3
Reference numeral 22 is configured so that the scraping ability is different.

As shown in FIG. 9, the scraping member 321 has a tip 321e provided at the tip of the arc-shaped wing 321b. On the other hand, the tip of the arc-shaped wing 322b of the scraping member 322 has no tip wing. Scraping member 32
The distance between the inner peripheral surface of the solid lid 32 and the inner peripheral surface of the solid lid 32 is formed narrower by providing the tip wings 321 e. Therefore, the scraping member 321 can scoop up the toner until the remaining amount of toner in the toner bottle 30 becomes smaller than the scraping member 322. That is, the scraping member 321 and the scraping member 322 are configured to have a difference in the scraping ability. Such a scraping member 321
When the remaining amount of toner in the toner bottle 30 decreases due to the configuration of the scraping member 322, the transport amount or the transport ratio does not suddenly decrease but gradually decreases.

In the above description, the replacement of the toner bottle 30 when the toner has been used up or the developing device 13
Is performed by opening the opening / closing lid CV of the apparatus main body shown in FIG. Further, in the above description, the scorotron charger 11 and the toner bottle 30 (in this case, the toner bottle 30 and the storage container, which are arranged on the upstream side of the developing device 13 in the rotation direction of the photosensitive drum 10 described in FIG. 1). It is also possible to integrate the mounting unit 40 with the developing unit 13 (in this case, the developing unit 13 and the storage container mounting unit 40 may be integrated) and exchange them together. It is.

As described above, the replenishment of the one-component developer from the developer accommodating container is favorably performed. However, the developer accommodating container, the accommodating portion for the accommodating container, or both can be separated from the one-component developing device. With this configuration, a small-sized one-component developing device incorporating a one-component developer (toner) is made possible, and the deterioration of the toner due to long-term stagnation of the toner in the one-component developing device is prevented. When the toner in the developer container (toner bottle) is used up, only the toner bottle is replaced. Further, the loss of toner is reduced according to the life of the one-component developing device, and the one-component developing device can be replaced. Further, by integrating the charging means and the developer container or the one-component developing device and exchanging them together, uneven charging due to contamination of the charging means, particularly toner contamination caused by the developing means disposed close to the charging means. Uneven charging can be prevented.

As described above, it is possible to provide an image forming apparatus in which the size of the one-component developing device can be reduced, the deterioration of the one-component developer can be prevented, and the replacement life of the one-component developing device can be optimized. .

[0071]

According to the present invention, the size of the one-component developing device can be reduced, the deterioration of the one-component developer can be prevented, and the replacement life of the one-component developing device can be optimized. Provision is possible.

[Brief description of the drawings]

FIG. 1 is a cross-sectional configuration diagram of a color image forming apparatus according to an embodiment of an image forming apparatus using a developing device according to the present invention.

FIG. 2 is an enlarged cross-sectional configuration diagram illustrating a developing device used in the image forming apparatus of the present invention and a first example of a developer storage container.

FIG. 3 is a schematic cross-sectional configuration diagram illustrating a second example of a developer storage container.

FIG. 4 is a perspective view of the developer container of FIG. 3;

FIG. 5 is a view showing a state where the developer storage container of FIG. 3 is mounted on a storage container mounting portion.

FIG. 6 is a diagram illustrating a movement path of toner from the developer storage container illustrated in FIG.

FIG. 7 is a front view of a solid lid of the developer storage container shown in FIG.

FIG. 8 is a right side view of the solid cover shown in FIG. 7;

FIG. 9 is a sectional view taken along the line II in FIG. 7;

FIG. 10 is a view showing a state in which the solid lid shown in FIG. 7 is rotated by 90 ° from FIG. 7;

[Explanation of symbols]

 Reference Signs List 10 photoconductor drum 11 scorotron charger 12 exposure optical system 13 developing device 14a intermediate transfer belt 14c primary transfer device 14f paper charger 14g secondary transfer device 14h transfer material static eliminator 15c timing roller 17 fixing device 30 toner bottle 131 developing sleeve 132 Supply roller 133 Blade 134 Stirring screw 600 Toner supply hopper LSa Level sensor Sa Interface

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H003 BB11 CC01 EE16 2H077 AA12 AA14 AB02 AB14 AC04 AD06 AE02 BA08 DA12 DA15 DA42 DA51 DB01 EA11

Claims (4)

[Claims] 1. A developer carrier that holds and rotates a thin layer of one-component developer, and a supply roller that supplies and recovers developer to and from the developer carrier, and stores the one-component developer. In the image forming apparatus having the one-component developing device, a level detecting unit for detecting a level of the one-component developer inside the one-component developing device is provided, and a developer accommodating container separable from the one-component developing device is provided. A one-component developer is supplied from the developer storage container in accordance with a detection level of the level detection means, and a level of the one-component developer in the one-component developing device is controlled to be constant. Image forming apparatus. 2. The image forming apparatus according to claim 1, wherein an upper portion of the supply roller is set at an interface position where the level of the one-component developer is controlled. 3. The image according to claim 1, wherein a stirring member is provided above the supply roller, and the surface of the one-component developer at the interface position is made uniform by stirring the stirring member. Forming equipment. 4. The image forming apparatus according to claim 1, wherein the developer container or the one-component developing device and a charging unit used for image formation are integrally formed. The image forming apparatus as described in the above.